Installation successful - activation successful - click icon to start Prepar3D_v3_Academic_3.4.22.19868 - message says " a problem caused the program to stop working correctly." Windows will close the program and notify you if a solution is available." Using Windows 10 64bit since it was released. What do I do now?

I deleted and re-downloaded from Lockheed Martin. Deleted previous download first. Installed new download. Same results.
What I did find interesting is: I installed in D:\ drive. But I found Prepar3Dv3 Add-ons in *both* C:\Program Files *and* D:\Program Files\Prepar3Dv3 Add-ons and D:\Program Files\Lockheed Martin\Prepar3D v3\Prepar3D v3 Add-ons. 3 different locations. I removed the folder in C:\ drive but it did not help anything. Followed the download and install pdf but no help.
Am I suppose to stop my firewall protection or something? Use BitDefented anti-virus. I looked in my regedit under Software. Found following: Lockheed Martin > Prepar 3Dv2 > Prepar 3Dv3 > Prepar 3DSDK. Underneath that folder was another Lockheed Martin Folder > Prepar 3D. Is this a issue? I do not have the v2 anymore. Is it safe to delete the Prepar 3Dv2 in the regedit? Any suggestions would be appreciated

Thank you so much for your reply. About the Blue Folders, I found 1 Prepar3D v3 files \ Prepar3D v3 Add-ons on C drive\Program Files. I found 1 Prepar3D v3 files \ Prepar3D v3 Add-ons on D drive\Program Files. And I found 1 Prepar3D v3 files \ Prepar3D v3 Add-ons inside the Installed P3D program itself. 3 different locations. Am I not allowed to install P3D in D drive under Program Files?? Is this the problem?? Again, many thanks for your help.

I have uninstalled for 3rd time now. This time I re-installed using default settings. Installation successful. Activation successful. Click desktop P3D icon - same error message: Lockheed Martin stopped working. A problem caused the program to stop working. Close Program. One friend I know said you are required to install the SDK first. Did not see
anything in install - uninstall pdf. Any comment or ideas??